The objective of the Microchemistry Core Facility (MCCF) is to support laboratory and clinical research programs at MSKCC by: (i) providing synthetic peptides and (ii) carrying out mass spectrometric (MS) and amino acid sequence analyses of proteins and peptides. Services are requested in writing; synthetic molecules are then made according to the specifications provided. Proteins submitted for identification or N-terminal sequencing are prepared by the laboratory requesting analysis. Special requests requiring the use of uncommon reagents / procedures, or that have the potential to become unusually involved or expensive, are discussed beforehand with facility management; different priority rules apply for such requests. Proper maintenance and optimization routines, and rigorous performance verification schedules and procedures have been developed for all instruments to minimize malfunctioning and to document instrument usage. Logs of completed services are kept in a database, necessary for preparing reports and to manage a charge-back system. To maintain services at the cutting-edge, MSKCC has created the "Proteomics R&D Lab" (PRDL) for regular transfer of new and improved technologies and methods (biochemical, mass spectrometric, informatics) to the facility. Future increases in protein identifications will be dealt with through: (i) our current approach of analyzing single (or mixtures up to three or four) proteins at a time, but at much higher volumes, and (ii) analyzing protein mixtures of medium complexity (up to 50 proteins) in a single, albeit more elaborate, analysis. Various aspects will be investigated and optimized for future upgrade of the service. During the previous grant period, polypeptide synthesis and analysis have contributed to the research endeavors of 47 different laboratories at MSKCC, as reflected in over 100 publications during 1996-2001 reporting on studies that utilized such services.